User name spiegel
Log entry time 16:56:43 on August20,2005
Entry number 152701
keyword=Tech'sI reproduced the problem with Q1. It would trip at appox. 1500 AMPS. I did a power supply "power off" (including UPS) Reset. Howerver, the problem remained. The saclay controls rack indicated a VS141 fault.
It is a lead voltage problem. I saw a 60 mv signal on the meter for VS141. I then ramped the magnet in local control to the previous failure level and monitored the lead voltage meter. It continued to increase to the threshold level until tripping the magnet between 70-80mv. I powered down supply and magnet and removed connector 03 at chassis C2D2 for VS141/VS142 lead voltage connection. Could not read any voltage at the connector. Replaced the connector and noticed the 60mv signal was gone. BAD CONNECTION !! I cleaned connector and recepticle with Gold Gaurd. Cleared all faults. Ramped magnet to 1643.*** AMPS for correct momentum and found the lead voltage increased to about 25-28mv with no voltage noise. Problem fixed.
FIGURE 1
